Thanks for the update french jurist, I did not know that legislation indeed changed.
It is pretty difficult to figure out such stuff since employees in banks, etc. are not much help.
For example I was told I can not get an usb-stick + chip for mobile internet with personal without a DNI. Then I saw that the line on the employee's form actually said "DNI / LC / [...] / Pasaporte", pointed at Pasaporte and suddenly he changed his mind. After almost a week of waiting, the line got activated too (in Austria the same thing took half an hour instead of days, but what counts is the result, isn't it?)
Different story but the bottom line is the same: They just don't know much on some topics and obviously better do nothing instead of risking to do something wrong. So the more info you have, the better you can talk to them.
On the topic of the costs: Most banks (at least in Austria) charge hefty transaction fees when transfering money to foreign countries. Even within the Euro-zone (where both sides use the same currency) it was quite bad until a law was passed to force equal treatment of transactions within the country and within the euro-zone. You might be better off looking which bank has the best conditions for foreign transactions to Argentina in your home country and make an account with them solely for the purpose of transfering to Argentina (depending on how much difference there is from one bank to another).
By the way, if one has a bank account in Argentina, which bank exchanges your home currency to pesos? The bank in your home country who sends the money or the bank in argentina who receives it? Not relevant to me because I neither have nor want a bank account here, but I always wanted to know the answer to that question.